Immunogold-silver staining of lymphocyte surface antigens on cells in suspension and in lymph node cryostat sections

An immunogold-silver staining (IGSS) technique for the light microscopical detection of leucocyte cell surface antigens in cell suspensions and cryostat sections is described. The specimens were first incubated with monoclonal mouse antibodies and then with colloidal gold-labelled goat anti-mouse antibodies. They were then immersed in a physical developer, counterstained and mounted. In light microscopy, the tissue architecture and the cellular morphology were well preserved. Positive cells showed dark granules on their surface membranes. Optimal labelling conditions were determined. This method proved to be a reliable tool for the enumeration of T-cells and their subsets in peripheral blood. The dense labelling permitted the use of panoptic counterstains like May-Grünwald-Giemsa or Wright's stain. This IGSS technique was used to determine the distribution of the T- and B-cell subsets in cryostat sections of reactive lymph nodes. The sensitivity of the method was comparable with that of immunofluorescence microscopy for cell suspensions and that of the biotin-avidin-peroxidase technique for tissue sections. Immunogold-silver staining was combined with enzyme cytochemistry. In dark-field or epipolarization microscopy the labelling appeared as bright granules on a dark background. With its dense granular membrane labelling and its good morphology IGSS is an ideal method for the study of particular cell types in mixed cell suspensions. In addition, it could be a general method for the detection of cell surface antigens in all kinds of cells and tissues.